KR20090017847A - Measuring system for optical lens and method for measuring characteristic of lens using the same - Google Patents

Abstract

A measurement system for an optical lens is provided to respectively adjust slopes of first and second holders and correct optical axes of a lens and a mirror or optical axes of the lens and an image sensor with accuracy to reduce measurement error of the system. A measurement system for an optical lens includes a first mount unit(M1), a second mount unit(M2) and a collimator(300). The first mount unit includes a first holder(100) and a first means(110). The first holder holds an optical element. The first means adjusts the slope of the first holder. The second mount unit is arranged above the first holder and includes a second holder(200) and a second means(210). The second holder holds an optical element. The second means adjusts the slope of the second holder. The collimator is located above the second holder.

Description

Measuring system for optical lens and measuring method of lens using the same {Measuring system for optical lens and method for measuring characteristic of lens using the same}

The present invention relates to a measuring system and a method of using the same, and more particularly, to a measuring system for an optical lens and a method for evaluating the characteristics of a lens using the same.

The reliability evaluation of an optical lens is to evaluate how deteriorated the characteristics of the lens in such an atmosphere after leaving the lens in a high temperature, high humidity or low temperature atmosphere. Under the above-described atmosphere, the thickness and refractive index of the lens may be changed, and as a result, characteristics such as the focal length of the lens may vary. In order to evaluate reliability, measurement equipment that can accurately measure the characteristics of the lens is required.

The metrology equipment described above may also be used for quality control of the lens. For example, by measuring the resolution of the lens before shipment using a predetermined measurement equipment, it is possible to determine the quantity and defect of the lens.

In recent years, as the high pixel size and miniaturization (i.e., the reduction of the overall length) of the optical lens proceeds rapidly, it becomes difficult to evaluate the characteristics of the lens and to control the quality. This is because the existing measurement equipment includes a large number of parts that depend only on processing precision, and thus the error of the equipment itself is large. Therefore, it is difficult to accurately and precisely evaluate reliability and control quality with existing measurement equipment. In addition, it is not easy to analyze the cause of the defect.

SUMMARY OF THE INVENTION The present invention has been made in an effort to improve the above-described conventional problems, and to provide a measurement system for an optical lens that can more accurately and accurately measure the characteristics of an optical lens.

Another object of the present invention is to provide a method for evaluating the characteristics of a lens using the optical system.

In order to achieve the above technical problem, the present invention includes a first mount unit including a first holder on which an optical element is mounted and a first means for adjusting the inclination of the first holder; A second mount unit disposed above the first holder and including a second holder on which the optical element is mounted and second means for adjusting the inclination of the second holder; And a collimator disposed above the second holder.

The first mounting unit may further include a moving device for horizontal and vertical movement of the first holder.

The first mount unit may have a structure in which the moving device, the first means, and the first holder are sequentially stacked.

The second mount unit may include a support pillar and a support plate extended in a direction perpendicular thereto, and the second holder may be provided on the support plate.

The second means may be provided between the support pillar and the support plate.

The second means may have the same structure as the first means.

The second mount unit includes a support plate for supporting the second holder, and the second means is a plurality of bolts provided in the second holder, the inclination of the second holder with respect to the support plate by the bolts. Can be adjusted.

The first and second mount units may be provided on the same base.

The base may be provided on another base.

A structure for supporting the collimator on the other base may be provided.

In order to achieve the above technical problem, the present invention is a base; A first mount unit provided on the base, the first mount unit including a first holder on which an optical element is mounted; And a second mounting unit provided on the base and including a second holder disposed above the first holder and mounted with an optical element, wherein the first and second holders are horizontal. It provides a measurement system for an optical lens.

The first mounting unit may further include a moving device for horizontal and vertical movement of the first holder.

In order to achieve the above another technical problem, the present invention is a first mounting unit comprising a first holder on which an optical element is mounted and a first means for adjusting the inclination of the first holder, disposed above the first holder and A second mounting unit comprising a second holder on which the optical element is mounted and a second means for adjusting the inclination of the second holder, and a metrology system for an optical lens comprising a collimator disposed above the second holder. A method for evaluating characteristics of a lens, comprising: leveling the first and second holders respectively; And evaluating characteristics of the lens using the collimator in a state in which mirrors and lenses are mounted on the first and second holders, respectively.

Leveling the first holder may include mounting a first mirror on the first holder; And a first phase in which light passing through a slit of the collimator is reflected by a beam splitter inherent to the collimator, and after the light is reflected through the beam splitter and reflected in the first mirror. And adjusting the first means to coincide with the center of the second phase reflected by the ray splitter.

Leveling the second holder may include mounting a second mirror on the second holder; And a first phase in which light passing through a slit of the collimator is reflected by a beam splitter embedded in the collimator, and after the light is reflected through the beam splitter and reflected in the second mirror. And adjusting the second means to coincide with the center of the second phase reflected by the ray splitter.

The metrology system for the optical lens may further comprise a moving device for horizontal and vertical movement of the first holder.

Evaluating characteristics of the lens may include evaluating characteristics of the lens before the reliability test; Performing a reliability test on the lens; Evaluating characteristics of the lens that have passed the reliability test; And comparing the characteristics of the lens evaluated before and after the reliability test.

In addition, in order to achieve the above another technical problem, the present invention provides a base, a first mount unit including a first holder on which the optical element is mounted as provided on the base, and the first as provided on the base A second mounting unit comprising a second holder disposed above a holder and mounted with an optical element, wherein the first and second holders are characterized in that the lens has a characteristic evaluation method using a measurement system for an optical lens. Centering the center of the first holder and the center of the second holder on a same vertical line; Mounting an image sensor and a lens on the first and second holders, respectively, and placing a subject above the second holder; Obtaining an image of the subject; And analyzing the image to evaluate the resolution of the lens.

The metrology system for the lens may further comprise a moving device for horizontal and vertical movement of the first holder.

The centering may be performed using the moving device and the tool microscope.

Before the centering step, it may further comprise the step of leveling the first and second holder, respectively.

In the measurement system of the present invention, since the inclination of the first and second holders can be adjusted, and the optical axis of the lens and the mirror or the lens and the image sensor can be precisely corrected, the measurement error of the equipment can be reduced. . Thus, using the metrology system of the present invention, optical properties such as focal length and resolution of the lens can be measured accurately and accurately.

Hereinafter, a measurement system for an optical lens and a method for evaluating characteristics of a lens using the same according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. The width and thickness of the layers or elements shown in the accompanying drawings are somewhat exaggerated for clarity of specification. Like reference numbers in the drawings indicate like elements.

1 shows a measuring system for an optical lens according to an embodiment of the present invention.

Referring to FIG. 1, first and second mounting units M1 and M2 are provided on a base 50. The first mounting unit M1 may include a moving device 120, a first means 110, and a first holder 100 that are sequentially provided on the base 50. The mounting portion 11 of the first holder 100 is mounted with an optical element such as a mirror or an image sensor. The first means 110 is a means for adjusting the inclination of the first holder 100. The first means 110 will be described later in more detail. The moving device 120 is a device for moving the first holder 100 in the horizontal and vertical directions. The moving device 120 may include X, Y, and Z axis moving units 120a, 120b, and 120c for moving the first holder 100 in the X, Y, and Z axis directions. X-, Y-, and Z-axis movement units 120a, 120b, and 120c may include X-, Y-, and Z-axis movement handles 10a, 10b, and 10c, respectively. The X-axis, Y-axis and Z-axis movement handles 10a, 10b and 10c are rotation elements, and by turning them, the first holder 100 can be moved in the X, Y and Z axis directions. Although not shown, each of the X-axis, Y-axis, and Z-axis moving units 120a, 120b, and 120c may include a precision length meter such as a micrometer. By means of the moving device 120 and the first means 110, the position and inclination of the first holder 100 can be arbitrarily adjusted.

The second mounting unit M2 includes a second holder 200 disposed above the first holder 100 and second means 210 for adjusting the inclination of the second holder 200. The second mount unit M2 may further include a support pillar 230 installed in the base 50 and a support plate 220 extended in a direction perpendicular thereto. The support plate 220 and the support column 230 may constitute a support structure having a 'a' shape when viewed from the side. The second holder 200 may be provided on the support plate 220, and the second means 210 may be provided between the support plate 220 and the support pillar 230.

The second holder 200 may be a rectangular or circular plate and has a predetermined opening 21 in the center thereof. The opening 21 is designed such that an optical element such as a lens or a mirror can be mounted. Another opening (hereinafter, referred to as a second opening) may be provided in a predetermined region of the support plate 220. It is preferable that the center of the second opening portion and the center of the opening portion 21 exist on the same axis. The second means 210 may be a predetermined tilting device having the same configuration as the first means 110. Although not shown, the second mounting unit M2 may further include a moving device for moving the second holder 200 in the horizontal and vertical directions.

A collimator 300 is present above the second holder 200. The collimator 300 includes a slit plate 31 having a predetermined slit and a beam splitter 32 below the slit plate 31. On the side of the collimator 300 there is an eyepiece 33 for observing the light reflected from the beam splitter 32. The slit may be in the form of a plurality of grid lines.

The structure 350 supporting the collimator 300 may have a shape similar to the letter 'c' when viewed from the side. The structure 350 may include another base (hereinafter, the second base) 310 and another support column (hereinafter, the second support column) 320 and another support plate (hereinafter, the second support plate) 330. . The second support pillar 320 is provided on the second base 310, the second support plate 330 is provided on the second support pillar 320, and the collimator 300 is disposed on the second support plate 330. Can be mounted. At least one of the collimator 300 and the structure 350 supporting the collimator 300 may further include tilting means (not shown) for adjusting the tilt of the collimator 300.

The base 50 provided with the first and second mounting units M1 and M2 may be placed and fixed on the second base 310 and may be separated from the second base 310.

Hereinafter, the first and second means 110 and 210 will be described in more detail.

FIG. 2 shows the first means 110 of FIG. 1 in detail.

Referring to FIG. 2, the first means 110 may include a lower plate 20a and an upper plate 20b. A support spring 30 and at least two horizontal adjustment screws 40 may be provided between the lower plate 20a and the upper plate 20b. The support spring 30 may be provided perpendicular to the lower plate 20a on the central portion of the lower plate 20a, and the horizontal adjustment screws 40 may be present at the edge of the first means 110. Horizontal adjustment screws 40 are a rotating element, by turning them can be arbitrarily adjusted the inclination of the first holder 100 of FIG.

The second means 210 of FIG. 1 may have the same structure as the first means 110 shown in FIG. 2. However, the structure and position of the second means 210 may vary. For example, the second means 210 may be a plurality of bolts provided in the second holder 200. Preferably, the bolts are at least three, and the bolts may be provided to be connected or contacted with the support plate 200 through the second holder 200. In this case, the inclination of the second holder 200 with respect to the support plate 220 can be adjusted by turning the bolts.

3A to 3C show a characteristic evaluation method of a lens according to an embodiment of the present invention. 3A and 3B are enlarged views of the image shown to the examiner through the eyepiece 33. In this embodiment, the measurement system of FIG. 1 is used.

Referring to FIG. 3A, in a state in which the first mirror 1 is loaded on the first holder 100, the inspector checks an image viewed through the eyepiece 33. At this time, the image shown to the examiner through the eyepiece 33 may be two kinds. One of them is the first crosshair c1 which appears when the incident light passing through the slit of the slit plate 31 of the collimator 300 is reflected by the beam splitter 32, and the other is the incident light passing through the slit. It is a second cross scale c2 which appears through the splitter 32 and is reflected by the first mirror 1 and then reflected by the light splitter 32. The first and second crosshairs c1 and c2 have the same shape, but the second crosshair c2 is smaller than the first crosshair c1, and the center of the second crosshair c2 is the first crosshair ( may be out of the center of c1). When the center of the second crosshair c2 is out of the center of the first crosshair c1 means that the first holder 100 and the collimator 300 are not parallel to each other. The examiner uses the first means 110 to adjust the inclination of the first holder 100 so that the center of the second crosshair c2 coincides with the center of the first crosshair c1. In this way, the first holder 100 can be leveled. In the enlarged view of FIG. 3A, the arrow indicates the moving direction of the second cross scale c2.

Referring to FIG. 3B, in a state in which the second mirror 2 is mounted on the second holder 200, the inspector checks the image seen through the eyepiece 33. In this case, the image shown to the examiner through the eyepiece 33 may be two kinds. One of them is the first crosshair c1 which appears when the incident light passing through the slit of the slit plate 31 of the collimator 300 is reflected by the beam splitter 32, and the other is the incident light passing through the slit. It is a third cross scale c3 which appears through the splitter 32 and is reflected by the second mirror 2 and then reflected by the light splitter 32. The first and third crosshairs c1 and c3 have the same shape, but the third crosshair c3 is smaller than the first crosshair c1, and the center of the third crosshair c3 is the first crosshair ( may be out of the center of c1). The center of the third crosshair c3 is out of the center of the first crosshair c1 means that the second holder 200 and the collimator 300 are not parallel to each other. The examiner uses the second means 210 to adjust the inclination of the second holder 200 so that the center of the third crosshair c3 coincides with the center of the first crosshair c1. In this way, the second holder 200 can be leveled. In the enlarged view of FIG. 3B, the arrow indicates the moving direction of the third cross scale c3. The order of implementation of steps 3A and 3B may be reversed. That is, step 3b may precede the step 3a.

As shown in FIGS. 3A and 3B, the first holder 100, the second holder 200, and the collimator 300 are parallel to each other by leveling the first holder 100 and the second holder 200, respectively. You can make it.

Referring to FIG. 3C, the first mirror 1 and the second holder 200 are mounted with the first mirror 1 and the lens 3 to be inspected, respectively. The focal length of the lens 3 is measured. To this end, the inspector may adjust the height of the first mirror 1 by using the Z-axis moving unit 120c. While adjusting the height of the first mirror 1, the focal length of the lens 3 can be measured by evaluating the sharpness of the cross scale reflected by the first mirror 1. In this case, the sharpness of the cross scale may be evaluated by the naked eye of the examiner, but may be evaluated by using a predetermined analyzer connected to the eyepiece 33. The inspector can evaluate how much the characteristics of the lens 3 have changed during the reliability test by measuring and comparing the focal length of the lens 3 before and after the reliability test.

Unlike the present invention, when using a measuring device in which the inclination of the first and second holders 100 and 200 cannot be adjusted, the horizontality of the first and second holders 100 and 200 is not precisely aligned. Since the evaluation of the characteristics of the lens is made in, it is difficult to accurately evaluate the characteristics of the lens.

Meanwhile, a precision centering step for placing the center of the first holder 100 and the center of the second holder 200 on the same vertical line may be further performed between steps 3b and 3c. The precision centering step may be performed using the tool microscope and the moving device 120. In more detail, after the base 50 provided with the first and second mounting units M1 and M2 is separated from the second base 310, the opening of the second holder 200 through the tool microscope ( The position of the first holder 100 is adjusted using the moving device 120 while looking down the mounting portion 11 of the first holder 100 and the lower portion 21). The opening 21 of the second holder 200 may be circular, and the mounting portion 11 of the first holder 100 may be a quadrangular shape, such that the center of the opening 21 and the center of the mounting portion 11 are coincident with each other. The precision centering may be performed by adjusting the moving device 120.

4A to 4C illustrate a method for evaluating characteristics of a lens according to another exemplary embodiment of the present invention. This embodiment is a modification of the method described with reference to Figs. 3a to 3c, the initial two steps of this embodiment are the same as Figs. 3a and 3b. Therefore, detailed description of the first two steps will be omitted.

After leveling the first and second holders 100 and 200, respectively, as shown in FIGS. 3A and 3B, the base 50 provided with the first and second mounting units M1 and M2 is disposed in the second base. Separate at 310. The separated base 50 and the first and second mounting units M1 and M2 provided thereon are shown in FIG. The structure of FIG. 4A may be a resolution measurement system according to an embodiment of the present invention.

Referring to FIG. 4B, the resolution measuring system of FIG. 4A is positioned in the observation device 500 equipped with the tool microscope 400. Then, while checking the positions of the first and second holders 100 and 200 using the tool microscope 400, the position of the first holder 100 is adjusted using the moving device 120. This is a precision centering process for placing the center of the first holder 100 and the center of the second holder 200 on the same vertical line, and may be the same as the precision centering process described above.

Referring to FIG. 4C, after the resolution measuring system is taken out of the observation apparatus 500, an image sensor 4 and a lens 5 to be inspected are respectively attached to the first and second holders 100 and 200. ), And a predetermined subject is positioned above the second holder 200. The subject may include a sheet 6 and a panel 7 to which the sheet 6 is attached. The sheet 6 may have various sizes of patterns. The patterns shown on the sheet 6 are imaged on a display device (not shown) connected to the image sensor 4 via the lens 5 and the image sensor 4. The resolution of the lens 5 may be evaluated by analyzing the image displayed on the display device. The analysis of the image may be performed in various ways, preferably using an analysis tool built in the display device.

If the horizontality of the first and second holders 100 and 200 cannot be precisely aligned, or if the optical axes of the lens 5 and the image sensor 4 cannot be precisely centered, the reliability of the resolution evaluation will be deteriorated. will be. This means that it is difficult to determine whether the lens is good or bad and that the cause of failure is not easy to analyze.

By using the method of the present invention, since the first and second holders 100 and 200 can be leveled and the optical axes of the lens 5 and the image sensor 4 can be precisely centered, The resolution of the lens 5 can be evaluated accurately and accurately.

While many details are set forth in the foregoing description, they should be construed as illustrative of preferred embodiments, rather than to limit the scope of the invention. Therefore, the scope of the present invention should not be defined by the described embodiments, but should be determined by the technical spirit described in the claims.

1 is a cross-sectional view showing a measurement system for an optical lens according to an embodiment of the present invention.

2 is a cross-sectional view showing a tilting means of the holder provided in the measurement system for an optical lens according to an embodiment of the present invention.

3A to 3C are cross-sectional views illustrating a characteristic evaluation method of a lens according to an exemplary embodiment of the present invention.

4A to 4C are cross-sectional views illustrating a characteristic evaluation method of a lens according to another exemplary embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

1: first mirror 2: second mirror

3, 5: lens 4: image sensor

10a: X axis movement handle 10b: Y axis movement handle

10c: Z axis moving handle 11: Mounting part

20a: lower plate 20b: upper plate

21: opening 30: spring

31: slit plate 32: light splitter

33: eyepiece 40: horizontal adjustment screw

50: base 100: first holder

110: first means 120: mobile device

120a: X-axis moving unit 120b: Y-axis moving unit

120c: Z-axis moving unit 200: second holder

210: second means 220: support plate

230: support pillar 300: collimator

310: second base 320: second support pillar

330: second support plate 350: structure

c1: first crosshair c2: second crosshair

c3: third crosshair M1: first mount unit

M2: second mount unit

Claims (21)

A first mounting unit comprising a first holder on which an optical element is mounted and first means for adjusting the inclination of the first holder; A second mount unit disposed above the first holder and including a second holder on which the optical element is mounted and second means for adjusting the inclination of the second holder; And And a collimator disposed above the second holder. The measurement system of claim 1, wherein the first mount unit further comprises a moving device for horizontal and vertical movement of the first holder. The measurement system for an optical lens according to claim 2, wherein the first mount unit has a structure in which the moving device, the first means, and the first holder are sequentially stacked. The measurement system of claim 1, wherein the second mount unit includes a support pillar and a support plate extending in a direction perpendicular to the support pillar, and the second holder is provided on the support plate. The optical system of claim 4, wherein the second means is provided between the support column and the support plate. 6. A measurement system for an optical lens according to claim 1 or 5, wherein said second means has the same structure as said first means. The method of claim 1, wherein the second mounting unit includes a support plate for supporting the second holder, the second means is a plurality of bolts provided in the second holder, with respect to the support plate by the bolts And the inclination of the second holder is adjusted. The measurement system of claim 1, wherein the first and second mount units are provided on the same base. 10. The system of claim 8, wherein said base is provided on another base. 10. The system of claim 9, wherein a structure for supporting the collimator is provided on the other base. Base; A first mount unit provided on the base, the first mount unit including a first holder on which an optical element is mounted; And A second mount unit provided on the base, the second mount unit being disposed above the first holder and including a second holder on which the optical element is mounted; And the first and second holders are horizontal. 12. The measurement system of claim 11, wherein the first mount unit further comprises a moving device for horizontal and vertical movement of the first holder. In the characteristic evaluation method of the lens using the measuring system for optical lenses of Claim 1, Leveling the first and second holders, respectively; And And evaluating characteristics of the lens by using the collimator in a state in which the mirror and the lens are mounted on the first and second holders, respectively. The method of claim 13, wherein leveling the first holder comprises: Mounting a first mirror on the first holder; And A first image in which light passing through a slit of the collimator is reflected by a beam splitter inherent to the collimator; and after the light is reflected from the first mirror through the beam splitter, And adjusting the first means such that the center of the second phase reflected by the ray splitter is matched. The method of claim 13, wherein leveling the second holder comprises: Mounting a second mirror on the second holder; And A first image of light passing through a slit of the collimator reflected by a beam splitter inherent to the collimator, and after the light is reflected from the second mirror through the beam splitter; And adjusting the second means such that the center of the second phase reflected by the ray splitter is matched. The method of claim 13, wherein the measurement system for the optical lens further comprises a moving device for horizontal and vertical movement of the first holder. The method of claim 13, wherein the evaluating characteristics of the lens comprises: Evaluating the characteristics of the lens before the reliability test; Performing a reliability test on the lens; Evaluating characteristics of the lens that have undergone the reliability test; And Comparing the characteristics of the lens evaluated before and after the reliability test. In the characteristic evaluation method of the lens using the measuring system for optical lenses of Claim 11, Centering the center of the first holder and the center of the second holder on a same vertical line; Mounting an image sensor and a lens on the first and second holders, respectively, and placing a subject above the second holder; Obtaining an image of the subject; And Evaluating the resolution of the lens by analyzing the image. 19. The method of claim 18, wherein the measurement system for the lens further comprises a moving device for horizontal and vertical movement of the first holder. 20. The method of claim 19, wherein the centering is performed using the moving device and a tool microscope. 19. The method of claim 18, further comprising leveling the first and second holders, respectively, before the centering step.

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